/*
 * Copyright 2002-2018 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.springframework.jms.support;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.core.Constants;
import org.springframework.jms.JmsException;
import org.springframework.lang.Nullable;
import org.springframework.util.Assert;

import javax.jms.Connection;
import javax.jms.ConnectionFactory;
import javax.jms.JMSException;
import javax.jms.Session;

/**
 * Base class for {@link org.springframework.jms.core.JmsTemplate} and other
 * JMS-accessing gateway helpers, defining common properties such as the
 * JMS {@link ConnectionFactory} to operate on. The subclass
 * {@link org.springframework.jms.support.destination.JmsDestinationAccessor}
 * adds further, destination-related properties.
 *
 * <p>Not intended to be used directly.
 * See {@link org.springframework.jms.core.JmsTemplate}.
 *
 * @author Juergen Hoeller
 * @see org.springframework.jms.support.destination.JmsDestinationAccessor
 * @see org.springframework.jms.core.JmsTemplate
 * @since 1.2
 */
public abstract class JmsAccessor implements InitializingBean {

    /**
     * Constants instance for {@code javax.jms.Session}.
     */
    private static final Constants sessionConstants = new Constants(Session.class);


    /**
     * Logger available to subclasses.
     */
    protected final Log logger = LogFactory.getLog(getClass());

    @Nullable
    private ConnectionFactory connectionFactory;

    private boolean sessionTransacted = false;

    private int sessionAcknowledgeMode = Session.AUTO_ACKNOWLEDGE;

    /**
     * Return the ConnectionFactory that this accessor uses for obtaining
     * JMS {@link Connection Connections}.
     */
    @Nullable
    public ConnectionFactory getConnectionFactory() {
        return this.connectionFactory;
    }

    /**
     * Set the ConnectionFactory to use for obtaining JMS {@link Connection Connections}.
     */
    public void setConnectionFactory(@Nullable ConnectionFactory connectionFactory) {
        this.connectionFactory = connectionFactory;
    }

    /**
     * Obtain the ConnectionFactory for actual use.
     *
     * @return the ConnectionFactory (never {@code null})
     * @throws IllegalStateException in case of no ConnectionFactory set
     * @since 5.0
     */
    protected final ConnectionFactory obtainConnectionFactory() {
        ConnectionFactory connectionFactory = getConnectionFactory();
        Assert.state(connectionFactory != null, "No ConnectionFactory set");
        return connectionFactory;
    }

    /**
     * Return whether the JMS {@link Session sessions} used by this
     * accessor are supposed to be transacted.
     *
     * @see #setSessionTransacted(boolean)
     */
    public boolean isSessionTransacted() {
        return this.sessionTransacted;
    }

    /**
     * Set the transaction mode that is used when creating a JMS {@link Session}.
     * Default is "false".
     * <p>Note that within a JTA transaction, the parameters passed to
     * {@code create(Queue/Topic)Session(boolean transacted, int acknowledgeMode)}
     * method are not taken into account. Depending on the Java EE transaction context,
     * the container makes its own decisions on these values. Analogously, these
     * parameters are not taken into account within a locally managed transaction
     * either, since the accessor operates on an existing JMS Session in this case.
     * <p>Setting this flag to "true" will use a short local JMS transaction
     * when running outside of a managed transaction, and a synchronized local
     * JMS transaction in case of a managed transaction (other than an XA
     * transaction) being present. This has the effect of a local JMS
     * transaction being managed alongside the main transaction (which might
     * be a native JDBC transaction), with the JMS transaction committing
     * right after the main transaction.
     *
     * @see javax.jms.Connection#createSession(boolean, int)
     */
    public void setSessionTransacted(boolean sessionTransacted) {
        this.sessionTransacted = sessionTransacted;
    }

    /**
     * Set the JMS acknowledgement mode by the name of the corresponding constant
     * in the JMS {@link Session} interface, e.g. "CLIENT_ACKNOWLEDGE".
     * <p>If you want to use vendor-specific extensions to the acknowledgment mode,
     * use {@link #setSessionAcknowledgeMode(int)} instead.
     *
     * @param constantName the name of the {@link Session} acknowledge mode constant
     * @see javax.jms.Session#AUTO_ACKNOWLEDGE
     * @see javax.jms.Session#CLIENT_ACKNOWLEDGE
     * @see javax.jms.Session#DUPS_OK_ACKNOWLEDGE
     * @see javax.jms.Connection#createSession(boolean, int)
     */
    public void setSessionAcknowledgeModeName(String constantName) {
        setSessionAcknowledgeMode(sessionConstants.asNumber(constantName).intValue());
    }

    /**
     * Return the acknowledgement mode for JMS {@link Session sessions}.
     */
    public int getSessionAcknowledgeMode() {
        return this.sessionAcknowledgeMode;
    }

    /**
     * Set the JMS acknowledgement mode that is used when creating a JMS
     * {@link Session} to send a message.
     * <p>Default is {@link Session#AUTO_ACKNOWLEDGE}.
     * <p>Vendor-specific extensions to the acknowledgment mode can be set here as well.
     * <p>Note that inside an EJB, the parameters to the
     * {@code create(Queue/Topic)Session(boolean transacted, int acknowledgeMode)} method
     * are not taken into account. Depending on the transaction context in the EJB,
     * the container makes its own decisions on these values. See section 17.3.5
     * of the EJB spec.
     *
     * @param sessionAcknowledgeMode the acknowledgement mode constant
     * @see javax.jms.Session#AUTO_ACKNOWLEDGE
     * @see javax.jms.Session#CLIENT_ACKNOWLEDGE
     * @see javax.jms.Session#DUPS_OK_ACKNOWLEDGE
     * @see javax.jms.Connection#createSession(boolean, int)
     */
    public void setSessionAcknowledgeMode(int sessionAcknowledgeMode) {
        this.sessionAcknowledgeMode = sessionAcknowledgeMode;
    }

    @Override
    public void afterPropertiesSet() {
        if (getConnectionFactory() == null) {
            throw new IllegalArgumentException("Property 'connectionFactory' is required");
        }
    }


    /**
     * Convert the specified checked {@link javax.jms.JMSException JMSException} to
     * a Spring runtime {@link org.springframework.jms.JmsException JmsException}
     * equivalent.
     * <p>The default implementation delegates to the
     * {@link JmsUtils#convertJmsAccessException} method.
     *
     * @param ex the original checked {@link JMSException} to convert
     * @return the Spring runtime {@link JmsException} wrapping {@code ex}
     * @see JmsUtils#convertJmsAccessException
     */
    protected JmsException convertJmsAccessException(JMSException ex) {
        return JmsUtils.convertJmsAccessException(ex);
    }

    /**
     * Create a JMS Connection via this template's ConnectionFactory.
     * <p>This implementation uses JMS 1.1 API.
     *
     * @return the new JMS Connection
     * @throws JMSException if thrown by JMS API methods
     * @see javax.jms.ConnectionFactory#createConnection()
     */
    protected Connection createConnection() throws JMSException {
        return obtainConnectionFactory().createConnection();
    }

    /**
     * Create a JMS Session for the given Connection.
     * <p>This implementation uses JMS 1.1 API.
     *
     * @param con the JMS Connection to create a Session for
     * @return the new JMS Session
     * @throws JMSException if thrown by JMS API methods
     * @see javax.jms.Connection#createSession(boolean, int)
     */
    protected Session createSession(Connection con) throws JMSException {
        return con.createSession(isSessionTransacted(), getSessionAcknowledgeMode());
    }

    /**
     * Determine whether the given Session is in client acknowledge mode.
     * <p>This implementation uses JMS 1.1 API.
     *
     * @param session the JMS Session to check
     * @return whether the given Session is in client acknowledge mode
     * @throws javax.jms.JMSException if thrown by JMS API methods
     * @see javax.jms.Session#getAcknowledgeMode()
     * @see javax.jms.Session#CLIENT_ACKNOWLEDGE
     */
    protected boolean isClientAcknowledge(Session session) throws JMSException {
        return (session.getAcknowledgeMode() == Session.CLIENT_ACKNOWLEDGE);
    }

}
